Machine and method of forming bands



1962 R. DISTEL ETAL 3,048,213

FORMING BANDS Aug. 7, 1962 R. DISTEL ETAL MACHINE AND METHOD OF FORMINGBANDS 3 Sheets-Sheet 2 Filed July 6, 1959 INVENTOR.

RICHARD DISTEL BY CHARLES F. HAUTAU ATTORNEY.

Aug. 7, 1962 R. DISTEL ETAL 3,048,213

MACHINE AND METHOD OF FORMING BANDS Filed July 6, 1959 3 Sheets-Sheet 3ATTORNEY This invention relates to a method of forming circul-ar bandsfrom sheet metal and to machinery for practicing this method. Moreparticularly it relates to a method and machinery for forming circularbrake bands.

Automatic transmissions usedon many contemporary vehicles incorporatecircular bands of sheet metal which are coated with a high frictionmaterial on their interior surfaces and act as brake bands. In certaintypes of brakes it is desirable that the band form an are somewhatsmaller than a complete circle. The need for the band being absolutelycircular in both instances is apparent, since it must mate with acircular member (brake drum) which has a friction coating on its outersurface. Any

irregularities in the circular shape of the band will pro-.

duce greater wear in particular spots and greatly shorten the life ofthe band.

The present invention contemplates a method of forming circular brakebands in an economical manner from sheet steel. It also contemplatesmachinery for practicing this method.

In one embodiment of the invention, which will subsequently be describedin detail, the band is formed from a strip of steel by two rollingoperations. In the first operation one end of a strip of steel of theproper dimensions is pushed through sets of rollers which are adjustedso as to produce a circular bend which has a slightly larger diameterthan the desired finished band. This circular bend is continued throughsomething less than 360 degrees of arc. The bent section is then cut oiffrom the main strip along a line transverse to the axis of the strip ata point adjacent to where the bend commences. The partially formed bandis then inserted in a second set of rollers which are powered .so as tocausethe band it brace int to be rotated through them and rebent so asto slightly decrease the diameter ends of the band to meet so that acomplete circular band is formed.

It has been determined that it is initially necessary to form thecircular band by pushing a strip through passive rolls so that the exactmeasurement of the length of the material incorporated in the band maybe made. Rolling the band to something less than a complete circular arcallows a cut-off to be made without disturbing the circularity of theband. If the band had been formed into a complete circle from apredetermined length of steel strip it would be extremely difficult toavoid fiattening its ends. Similarly, if it were necessary to cut offthe band before inserting it into the roll, expensive ma terial handlingtechniques would be necessary.

The machine may be considered as consisting of four sections. The firstsection, generally indicated at 16, received an elongated strip 12 ofsheet metal from a coil or similar supply source (not shown). isoperative to straighten the strip 12 through a series of rolls and tofeed a precisely measured length of the strip into a passive rollsection, generally indicated at 14. The passive roll section 14 formsthe strip 12 into an incomplete -(preferably approximately 320 degrees)circular section having a radius greater than that of the desiredfinished roll. The passive roll section 14 also provides a cut-oildevice which separates the partially formed band from the strip 12 anddelivers it to the poweredroll section of the machine, generallyindicated at 16, by means of a delivery chute 18. The section 16includes means for properly orienting the partially formed band, forfeeding the band to a series of powered rolls, and for rerolling Thesection .10

the partially formed hands into a complete circular band of smallerradius.

The straightening and feeding portion of the machine 10 is generallysupported on a base 20 which is formed of welded sheet steel as themajor portion of the supporting structure to be described. The base 20supports an electric motor 22 and an hydraulic pump 24 driven by themotor. This source of hydraulic power energizes the entire machine. Theconnecting hydraulic lines are not shown in the drawings or described astheir nature is well known to those skilled in the art. A hydraulic flowcontrol valve 28 is provided which may be manually adjusted to providethe desired full volume.

Similarly the electrical circuitry, which is housed in a control cabinet26 supported on the base 20, is of the type generally associated withsuch machinery and the particular electrical inter-connections will notbe described.

It is therefore seen to be an object of the present invention to providea method of forming circular bands of sheet steel which will allow acomplete closed band to be formed with no deviations from true circularform.

Another object is to provide machinery to economically practice suchmethod.

A further object of the present invention is to provide a method offorming complete circular bands of sheet steel which comprises the stepsof initially forming a partial circular band of a greater radius thanthe desired finished band from an elongated strip of stock, cutting oilthe partial circular band from the remainder of the stock, and rerollingthe band to diminish its radius and form a complete circle.

Another object of the present invention is to form a completely circularband through the method of initially pressing a strip of stock through aseries of passive rolls in order to form a partial circular band havinga greater diameter than that of the desired finished band, cutting offthe partially formed band from the remainder of the strip of stock, andrerolling the partially formed band through powered rolls in such manneras to diminish the diameter and form a complete circular band.

Another object of the present invention is to provide apparatus inaccordance with the above objects which includes means for correctingthe tendency of the passive rolls for warping the material about an axistransverse to its length.

Another object of the present invention is to provide apparatus inaccordance with the previous objects wherein the material isautomatically handled between operations.

A further object is to provide apparatus in accordance wtih the previousobject utilizing means for precisely measuring the length of strip whichis fed through the passive rolls in order to form partial circular formwhich is then rerolled to form the final enclosed form.

Other objects, advantages and applications of the present invention willbe made apparent by the following detailed description of a preferredembodiment of the invention. The description makes reference to theaccompanying drawings in which:

FIGURE 1 is a perspective view of a machine embodying the presentinvention;

FIGURE 2 is a plan view of a portion of the machinery which initiallyrolls the band;

FIGURE 3 is a plan view of the machinery of FIG- URE 2 taken along lines33 of that figure;

FIGURE 4 is a plan view of the machinery which re rolls the bend in sucha manner as to complete it;

FIGURE 5 is an elevation view of the machinery of FIGURE 4; and

FIGURE 6 is a perspective view of a partially formed band.

An electric push button panel provides selective start and stop controlover all of the elements of the machine as well as allowing start andstop control over an automatic routine whereby the operations which willbe subsequently described are performed automatically in their propersequence.

The strip 12 first enters the machine through a pair of locating rolls34 which are supported on a sub-base 32. These rolls maintain the strip12 in general vertical alignment for feeding through the machine. Thestrip 12 then passes between two horizontal guide blocks 36 which may beadjusted along a bar 38 extending transversely to the direction of feedof the strip 12 and having a T slot 40 in which the blocks 36 move.

The strip 12 then passes through a series of straightening rolls 42which are disposed in a support member 44. These rolls act to remove anykinks from the strip. After passing through the roll housing 44 thestrip 12 is again aligned in a horizontal plane by a pair oftransversely adjustable guides 46 which are supported in a block ashaving a T slot 50 along which the guides 46 may be moved. The strip 12next passes through a pair of longitudinally disposed retaining blocks52. The blocks 52 are disposed parallel to one another and have recessescut in their opposed surfaces. The edges of the strip 12 passes throughthese recesses so that the blocks 52 act to guide the strip over aportion of its length.

After passing through the guide blocks 52 the strip 12 passes between apair of passive warping rollers 54 and 56 which have conjugate surfacesthat are slightly lower at their center point than at their ends. Thatis, the lower roller 56 is concave while the upper roller 54 is convex.The spacing between the rollers may be adjusted by means of anadjustment nut 58 which moves the upper roller 54 in a vertical plane.These rollers therefore give the strip 12 a bowed cross-section with alow point at the center. This action corrects for the tendency for thesubsequent rolls to how the strip with the high point at the center. Itproduces a completely rolled strip that is absolutely fiat in thetransverse direction.

The strip next passes between a fixed lower roll 60 and two adjustableupper rolls 62. The rolls 62 are supported in a block 64. Spacing ofthis block 64 with relation to the rest of the machine may be adjustedby moving a wedge-shaped block 66 in a transverse direction through useof a hand wheel 68. The shaft of the wheel 63 is threaded and isattached to the block 66 by means of a connecting bar 72. Therefore,when the hand wheel 68 is rotated the shaft 70 moves transversely withinits supporting block 74 and moves the wedge 66 which adjusts the block64 in a direction perpendicular to the strip 12. The position of theroller 62 may be locked by means of a second hand wheel 76 which alsothreads on the shaft 70 and looks it against block 74.

The lower roll 60 extends into the space between the upper rolls 62 insuch a manner as to bend the strip in a downward direction as it isforced between the rolls. By adjusting the exact height of the rolls 62by means of the hand wheel 68 the exact diameter of the bend may becontrolled.

The mechanism which forces the strip through the various rolls whichhave been indicated will now be described. Two hardened and groundshafts 86 are supported along opposite sides of the guide strips 52 atapproximately the same height as the guides. The shafts 80 are fixedlysupported above the sub base 32 by support members 82. Ball bushingguide members 84 surround each of the shafts and act to support a bridgemember 86 between them. The bridge member 86 has a central aperturethrough which the guide bars 52 pass. On the top side of the bars itsupports a hydraulic cylinder 88 which has shaft 90 journaled in abushing 92. The shaft 99 has a flattened section 94 at its lower endwhich passes between the guide strips 52. The lower side of the bridgecarries a block member 96. When the cylinder 98 is actuated so as toextend its rod 90 the strip 12 is captured between the lower end 94 ofthe rod 96 and the block 96. The entire bridge assembly 86 is then movedalong the shafts 30 under the influence of a hydraulic cylinder 98 whichhas its rod 100 connected to the bridge member 86. The cylinder 93 isdisposed in an aperture beneath the rolls 34- and 44 on the sub base 32.When the cylinder 98 extends its rod 160 the entire bridge assem blymoves toward the left as viewed in FIGURES 1, 2 and 3. The cylinder 88has its rod extended at that time and it moves the strip 12 with it,passing the strip through various rolls.

At the left termination of the guides 52 another hydraulic cylinder 102is disposed with its rod 104 in a vertical position. The cylinder 102 issupported above the guides 52 on a block 1136. When the rod of thecylinder 162 extends it captures the strip 12 against a lower bearingblock 108.

The manner in which the initial roll is formed in the strip is thereforeas follows. The bridge member 86 and its cylinder 88 are initiallydisposed in their far right position, that is, with the rod 160 of thecylinder 23 fully retracted. The control circuitry then directs a fluidflow to the cylinder 88 causing to extend its rod 90 so as to capturethe strip 12 between the'rod section 94 and the block 96.

The cylinder 96 is then energized to cause its rod 1% to extend and tomove the bridge toward the left, to the position shown in FIGURES 2 and3. As this is done the strip 12 is drawn from its supply reel throughthe straightening rolls 42. The guides 34 and 36 act to maintain it in aproper disposition for entry into the straightening rolls. Its other endis passed through the warping rolls 54 and 56 and the bend rolls 6!} and62. The end which has passed through the bending rolls 69 and 62 is bentin a downward, counter clockwise direction so as to partially surroundthe form which supports the roll 69.

The end of motion of the bridge 86 is signaled by a limit switch 112which is tripped by an arm 114 extending from the bridge, the switch 112acts through the control circuitry to halt the motion of the cylinderrod 196. Similarly, in the extreme right position the arm 114 actuatesthe limit switch 116. The distance between these limit switches is equalto the length of the strip which is passed through the rolls by onemotion of the bridge 66.

When the bridge has reached its extreme left position the hydrauliccylinder 162 is energized and extends its rod to clamp the strip 12. Thecylinder 88 is then de-energized and the cylinder 98 is energized so asto retract its rod and bring the bridge 86 back to its initial position.During this time the strip is maintained in position by the cylinder102.

After the bridge 86 has moved a section of the strip through the rolls6t and 62, that rolled section may be cut off from the main strip. Thisis done by a cutter 113 (FIGURE 3) which is carried in a support 114which is hollowed for weight reduction and actuated by rod 116 of ahydraulic cylinder 118. The cylinder 118 acts in conjunction with acylinder 120 in an hydraulic intensifier circuit such as is well knownto those skilled in the hydraulic art to give a powerful stroke to thecutter 113. The cut-off of the strip 12 is at right angles to itslength.

After the paritally formed band, indicated at 122, is cut off from thestrip 12, it falls over the form 111] and is gravity fed into the chute18. As its left most edge strikes the angle 124 of the chute it ispivoted about its lower point so that it rolls down the final section ofthe chute.

At the end of the chute it comes to rest'on a pair of bars 126 which aresupported in parallel position across an opening 128 in the base 130 ofthe rerolling section 16 of the machine. As the partially formed bandrests on the bars 126 it contacts a pair of rubber rollers 132 which maybe revolved by an electric motor 134 through enclosed belt arrangement136.

The rolls 132 cause the partially formed band to rotate in a clockwisedirection as viewed from the left of the figures. The motor is socontrolled that the rotation continues for 360 degrees. At some point inthis rotation the edge of the partially performed band abuts against astop block 138 which is pivotably supported on an arm 140 above the base130. The stop prevents the band from rotating further and causes it tofrictionally slide over the rolls 132. During this rotation a plate 142which is also supported on the arm 140 prevents the band from falling tothe left in the drawing. The band is supported on the right by a pusherplate 144.

The stop 138 acts to orient the band with respect to the machine. Afterthe orientation has been accomplished the pusher block 144, which rideson two horizontal rods 146 that are supported in bushings 148, is movedto the left in the drawings under the influence of an hydraulic cylinder150. The cylinder 150 is supported on a shelf 152 on the end of the base130.

The pusher block 144 acts to move the band to the left in the drawingsalong the shafts 126. One end of the band thereby comes to rest betweena power roller 154 and three passive rollers 156. The passive rollersare arranged about the powered roller so that a band rolled between themwill assume their final proper diameter.

The three passive rollers may be moved between an operating positionwherein they are disposed in close proximity to the power roller 154,and an open position wherein they are removed from the power roller 154so that a band may be inserted or removed from between them, by ahydraulic cylinder 158. The two side pas sive rollers 156 may beindependently adjusted as to their closed position by a hand wheel 160.The wheel operates through gearing (not shown) to move the two outsiderollers independently of the center roller so as to vary the diameterband which will be formed between the rollers.

The roll 154 is powered by a motor 162 which acts through a right anglereducer drive 164. The output shaft 166 of the drive 164 is connected tothe roller 154 through the circumference of the desired finished handthrough a plurality of passive rolls adapted to form a circle of greaterradius than said desired finished band; severing said rolled portionfrom said strip at a point which has been passed through said passiverolls; transferring said cut off large radius band to a plurality ofpowered rolls; and rerolling said large radius band so as to reduce itsradius.

2. The method of forming complete circular bands of metal strip fromlength of strip stock which is longer than the circumference of thefinished band, comprising: passing a predetermined length of strip stockequal to the circumference of the desired finished band through theaperture presented by a first pair of passive rollers at one side of thestock and a second passive roller on the other side of said stock so asto form a circle of greater radius than said desired finished band;severing said rolledportion from said strip at a point which has beenpassed through said rolls; and rerolling said large radius band so as toreduce its radius.

References Cited in the file of this patent UNITED STATES PATENTS1,783,047 Marshall NOV. 25, 1930 1,791,257 Ziler Feb. 3, 1931 1,939,577Sneed Dec. 12, 1933 1,973,436 Hjort Sept. 11, 1934 2,742,078 WilliamsApr. 17, 1956

